- "Torture has never been a reliable means of extracting information. It is ultimately self-defeating as a means of control. One wonders it is still practiced."
- —Jean-Luc Picard, 2369[src]
Torture was the practice of inflicting physical or psychological pain on a captured subject. Torture was used by many species of the universe between and during conflicts on prisoners or captives of high value. Torture was also used as a punishment for crimes committed by prisoners.
During Earth's second World War, the Schutzstaffel and Gestapo of Nazi Germany would use torture in their interrogations of prisoners. This practice was also used by the Nazis and SS of Ekos in the 23rd century. (TOS episode: "Patterns of Force"; ENT episode: "Storm Front")
In the 22nd century, the Suliban Cabal would torture people for information regarding the Temporal Cold War and other conflicts related to it. The Andorian Guard would rely on torture. Humans, they would beat to a pulp. On Vulcans, they would use a device that would cause a Vulcan to lose control of their emotional barrier. During the Xindi incident, Enterprise (NX-01)'s captain Jonathan Archer used an airlock to get information out of an Osaarian pirate. Commander Guruk Dolim interrogated and tortured Archer. When several of Doctor Arik Soong's Augments attacked Cold Station 12, Dr. Jeremy Lucas refused to give them the access codes to the other augment embryos. Soong then had Lucas' assistant exposed to the Symbalene blood burn. When Lucas continued to refuse, the Augments then placed the Enterprise's CMO, Dr. Phlox in the exposure chamber. Lucas complied and gave the codes. (ENT episode & novelization: Broken Bow; ENT episodes: "Shockwave", "The Andorian Incident", "Kir'Shara", "Anomaly", "Cold Station 12")
In the 23rd century, Captain James T. Kirk and other members of the USS Enterprise crew endured torture by men such as Tristan Adams, Garth of Izar and the Vians. (TOS episodes: "Dagger of the Mind", "The Empath", "Whom Gods Destroy")
In the 24th century, the Cardassian military used various methods of torture during the Occupation of Bajor and it's war with the Federation. The Obsidian Order also used torture on their own people like Procal Dukat. Even after the end of the war, the Cardassians would torture Federation prisoners such as Jean-Luc Picard and Miles O'Brien. In the Delta Quadrant, the Kazon and Mokra Orders would torture their prisoners in order to get information. (TNG episodes: "Ensign Ro", "Chain of Command"; DS9 episodes: "Tribunal", "The Die is Cast", "Inter Arma Enim Silent Leges", "Duet", "The Wire", "For the Cause"; VOY episodes: "Maneuvers", "Resistance")
Following the arrival of Captain Nero and his ship, the Narada, he and his crew were captured by the Klingons and taken to Rura Penthe. For the next 25 years, Nero was interrogated by the Klingons, who used Centaurian slugs on him. They eventually learned that Nero was from the the future and was awaiting the arrival of Ambassador Spock. (TOS movie, novelization & comic adaptation: Star Trek (deleted scene(s)); TOS comic: "Nero")
Nero and crew then made their escape and retook the Narada. Following the Destruction of Vulcan, Nero then forced the USS Enterprise's captain, Christopher Pike, to give him the frequencies for Earth's Border protection grid. Pike refused until Nero used the Centaurian slugs on him.(TOS movie, novelization & comic adaptation: Star Trek)